Bicycles have been enjoyed as a source of transportation and pleasure for well over one hundred years. Over this time period, many adaptations have been made to conform bicycles to specific uses, render their use safer and more comfortable, and to increase the efficiency of the energy applied to the vehicle by the rider. In substantially all bicycles, movement of the bicycle is caused by the rotation of a bicycle crank which is typically connected to a sprocket, which in turn is linked via a chain to a wheel. Rotation of the bicycle crank by the rider's legs causes the sprocket to rotate thereby driving the chain and consequently a wheel.
Those skilled in the art will appreciate that the amount of torque applied by the crank arms is directly related to the distance between the axis about which the crank arm rotates and the position on the crank arm where force is applied by the rider, e.g. the axis about which a bicycle pedal rotates. A number of different devices have been disclosed to permit the adjustment of the bicycle pedal position relative to the axis of rotation of the pedal crank. One disadvantage of many previously disclosed devices is the number of pieces employed. Those familiar with bicycle riding appreciate that there is a significant amount of vibration imparted to the entire bicycle during riding. Therefore, it is desirable to minimize the number of connections which may be loosened due to vibrations.
It would therefore be desirable to provide a simple, one-piece bicycle crank which permits the angle of torque application and the actual torque applied to a bicycle crank to be arranged in a manner which is simple and which does not sacrifice or detract from the strength of the crank.
It would also be desirable to provide a bicycle crank which tends to decrease the "dead zone", i.e. when one pedal is around the 12 o'clock position and the opposite pedal is around the 6 o'clock position.